On 20/08/14 15:43, Les Mikesell wrote: > On Wed, Aug 20, 2014 at 8:25 AM, Toralf Lund <toralf.lund at pgs.com> wrote: >> On 19/08/14 20:33, John R Pierce wrote: >>>>>>>> If i should install both java 1.6 and 1.7 , how to do that ? >>>>>> I don't know whether you*should* do it, not knowing much about your >>>>>> setup, but assuming CentOS 7, I think you can install both the >>>>>> java-1.6.0-openjdk and java-1.7.0-openjdk packages. >>>> I can confirm that. I have both installed. You can configure the default >>>> using the 'alternatives' system. >>> is it just me, or does anyone else think that 'alternatives' system is >>> completely bogus? >> I've always seen it as designed mostly for system services for which >> there are several common implementations - like the SMTP server or the >> printing system. Where I think it makes sense. > But do you really need _two_ symlinks to get a default in your PATH? I think the argument is that "configuration" commands shouldn't change bin directories. Which is right in a way, but maybe this is one of the cases where practicality should have been chosen over formal correctness. > >> It may also be useful to be able to set up a system-wide default for >> user applications "with alternatives", but I suppose a user override >> ought to be possible in that case. >> >>> what if I have one user that wants JDK6 and another that needs JDK7 ? >> I guess the "preferred applications" system in the desktop is in a way >> meant for such cases, but this of course comes across as incomplete, too. >> > The concept used for 'software collections' is a more realistic > approach - but instead of hiding where things land and needing a tool > to set up use, why not just tell people what to add to their own PATH > and LD_LIBRARY path to get the version you want. That's almost > certainly what the developers of every package where they need to have > test versions does. So why treat the users like they would be too > dumb for that? That's a point. You could also easily develop "config" tools that would make that job easier for "dumb" users - this might be more productive than maintaining different solution that essentially have the same effect. - Toralf > This e-mail, including any attachments and response string, may contain proprietary information which is confidential and may be legally privileged. It is for the intended recipient only. If you are not the intended recipient or transmission error has misdirected this e-mail, please notify the author by return e-mail and delete this message and any attachment immediately. If you are not the intended recipient you must not use, disclose, distribute, forward, copy, print or rely on this e-mail in any way except as permitted by the author.